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Induction of micronuclei and nuclear abnormalities in Oreochromis niloticus following exposure to petroleum refinery and chromium processing plant effluents.

The genotoxic effects of effluents from a petroleum refinery and a chromium processing plant were evaluated in Oreochromis niloticus (Pisces: Perciformes) using the micronucleus test. Fish were exposed to different concentrations (5, 10 and 20%, v/v) of the effluents for 3, 6 and 9 days. Micronucleus analyses were carried out on gill epithelial cells and peripheral blood erythrocytes. Nuclear abnormalities other than micronuclei, considered as genetic damage indicators, were also evaluated on erythrocytes. Cyclophosphamide at a single dose of 4 mg/L was used as a positive control. The results of this study showed that both effluents had genotoxic potential. On the other hand, the level of genetic damage induced by petroleum refinery effluent was considerably higher than that of chromium processing plant effluent. Our results further indicate that nuclear abnormalities other than micronuclei, such as blebbed and lobed nuclei, may also be used as indicators of genotoxic damage.

Analysis of Variance↗

Combustion characteristics of a turbocharged DI compression ignition engine fueled with petroleum diesel fuels and biodiesel.

In this study, the combustion characteristics and emissions of two different petroleum diesel fuels (No. 1 and No. 2) and biodiesel from soybean oil were compared. The tests were performed at steady state conditions in a four-cylinder turbocharged DI diesel engine at full load at 1400-rpm engine speed. The experimental results compared with No. 2 diesel fuel showed that biodiesel provided significant reductions in PM, CO, and unburned HC, the NO(x) increased by 11.2%. Biodiesel had a 13.8% increase in brake-specific fuel consumption due to its lower heating value. However, using No. 1 diesel fuel gave better emission results, NO(x) and brake-specific fuel consumption reduced by 16.1% and 1.2%, respectively. The values of the principal combustion characteristics of the biodiesel were obtained between two petroleum diesel fuels. The results indicated that biodiesel may be blended with No. 1 diesel fuel to be used without any modification on the engine.

Gasoline↗

The application of bioassays as indicators of petroleum-contaminated soil remediation.

Bioremediation has proven successful in numerous applications to petroleum contaminated soils. However, questions remain as to the efficiency of bioremediation in lowering long-term soil toxicity. In the present study, the bioassays Spirotox, Microtox, Ostracodtoxkit F, umu-test with S-9 activation, and plant assays were applied, and compared to evaluate bioremediation processes in heavily petroleum contaminated soils. Six higher plant species (Secale cereale L., Lactuca sativa L., Zea mays L., Lepidium sativum L., Triticum vulgare L., Brassica oleracea L.) were used for bioassay tests based on seed germination and root elongation. The ecotoxicological analyses were made in DMSO/H2O and DCM/DMSO soil extracts. Soils were tested from two biopiles at the Czechowice oil refinery, Poland, that have been subjected to different bioremediation applications. In biopile 1 the active or engineered bioremediation process lasted four years, while biopile 2 was treated passively or non-engineered for eight months. The test species demonstrated varying sensitivity to soils from both biopiles. The effects on test organisms exposed to biopile 2 soils were several times higher compared to those in biopile 1 soils, which correlated with the soil contaminants concentration. Soil hydrocarbon concentrations indeed decreased an average of 81% in biopile 1, whereas in biopile 2 TPH/TPOC concentrations only decreased by 30% after eight months of bioremediation. The bioassays were presented to be sensitive indicators of soil quality and can be used to evaluate the quality of bioremediated soil. The study encourages the need to combine the bioassays with chemical monitoring for evaluation of the bioremediation effectiveness and assessing of the contaminated/remediated soils.

Biological Assay↗

Identification of alkyl carbazoles and alkyl benzocarbazoles in Brazilian petroleum derivatives.

Carbozoles are important compounds in crude oils, as they may be used as geochemical tracers, being the major type of nitrogen compounds in petroleum. At the same time, they are regarded as undesirable due to the problems they may cause in the refining process, such as catalyst poisoning, corrosion, gum or color formation in final products. As separation and identification of carbazoles are challenging goals, this work presents a chromatographic method, made of a pre-fractionation on neutral alumina followed by the separation and identification of two classes of carbazoles using FeCl(3)/Chromossorb W and gas chromatograph with mass spectrometer (GC/MS) (SIM-single ion monitoring mode) analysis. For the first time, a series of alkyl carbazoles and alkyl benzocarbazoles were identified in heavy gas oil (HGO) and atmospheric residue of distillation (ARD) obtained from Brazilian petroleum.

Aluminum Oxide↗

Joint chemical flushing of soils contaminated with petroleum hydrocarbons.

How to increase the efficiency of chemical flushing and decrease the remediation expenses of contaminated soils are two key scientific and technological issues to be solved. Joint chemical flushing was tested and compared with the water-flushing. The joint acid-flushing could effectively remove petroleum hydrocarbons in contaminated aquorizem and the dosage of washing powder as a flushing agent was greatly reduced, thereby, saving approximately 1200 US dollars of expenses relative to the water-flushing. The joint salt-flushing could be an optimal method for the cleanup of meadow burozem contaminated with petroleum hydrocarbons under the experimental conditions. Moreover, the amount of surfactant remained in the two washed soils after the joint acid-flushing and the joint-salt-flushing was minimal.

Acetates↗

Managing disposal of water produced with petroleum in Kuwait.

Disposal of water produced with petroleum has been of great interest in Kuwait for the last 20 years. The current problem arose when the Burgan oil field, which is the second largest field in the world, experienced successive increases in the water content of the produced oil. This study introduces a decision-making analysis of the considered alternatives for the disposal of the produced water. Four alternative solutions exist for the industry as practical solutions for the disposal of water produced in Kuwait. The first method utilizes a large number of pits to discharge water. The second alternative depends on discharging water into sealed pits. The third approach to dispose water is by injecting the water underground. The last method is similar to the previous one, but takes into consideration the recovery of reservoir pressure to maintain the rate of oil production. A questionnaire was distributed to 48 experts at the top management level of the petroleum companies and the governmental authority. The data collected considered cost, efficiency, and environmental parameters. Based on the data, a statistical analysis was conducted using the factor analysis method to reduce the number of investigated variables. The analysis concluded that the optimal solution is to use the effluent injection method to discharge water produced with oil in Burgan and similar fields in Kuwait.

Data Collection↗

Petroleum hydrocarbon residues in the marine environment of Bassein-Mumbai.

The paper reports PHc contamination in water, sediment and biota of the coastal area of Bassein-Mumbai in relation to relatively less polluted sites (Dabhol and Ratnagiri) off the west coast of India. To facilitate inter-comparison three standards have been used though the results are reported in terms of SAM (Residue of Saudi Arabian Mix crude). The concentration of PHc in water off Bassein-Mumbai varies widely (2.9-39.2 microg l(-1)) as compared to the average baseline (2.8 microg l(-1)) with higher values generally confined to creeks and estuaries. The higher concentration of PHc in the bottom water of shallow areas is attributed to the contribution from the sediment-associated petroleum residue. High concentration of PHc in the surficial sediment of inshore area Ratnagiri (107.7 ppm, dry wt) is perhaps the remnants of an oil spill that occurred in the Bombay High region on May 17, 1993. The majority of values of PHc concentration in the surficial sediment of the Bassein-Mumbai region exceed 15 ppm (dry wt) against the expected background (<3 ppm, dry wt) and the trend is indicative of transfer of PHc loads from the inshore areas to the open-shore sediments. The PHc concentration of 0.8-2.6 ppm (dry wt) in sediment deposited prior to the first global commercial use of petroleum in core R5 represents the biogenic background. Based on the period of industrialisation and the horizon of PHc accumulation, a sedimentation rate of 0.2 and 1.0 cm y(-1) respectively is estimated for cores U11 and U12. Substantial increase in the concentration of PHc in sediment after 1950 in cores T8 and T10 correlates well with the establishment of refineries on the western shore of the Thane Creek in 1955-1960. A minor peak in most cores in the top 10 cm sediment probably results from biological transfer of PHc lower into the sediment by benthic organisms. Excess of PHc retained in the sediment of the Bassein-Mumbai region over the biogenic background is estimated at 40,000 t. The PHc residues (1.8-10.8 ppm, wet wt) in fish caught off Bassein-Mumbai do not suggest bioaccumulation.

Animals↗

Polycyclic aromatic hydrocarbon 13C/12C ratio measurement in petroleum and marine sediments application to standard reference materials and a sediment suspected of contamination from the Erika oil spill.

This paper describes a simple and rapid sample preparation procedure allowing to measure the stable carbon isotopic composition of polycyclic aromatic hydrocarbons (PAHs) in petroleum and in sediments. The aromatic fraction is first purified and isolated on alumina and silica micro-columns. A high-performance liquid chromatography fractionation allows one then to isolate each aromatic family in order to limit coelutions between PAHs. Moreover, this purification step reduces the importance of the unresolved complex mixture which otherwise contribute to the GC-isotope ratio MS background signal. The application of this analytical procedure has allowed one to determined PAH isotopic composition in a reference material crude oil (SRM 1582) and a marine sediment (SRM 1944) with good reproducibility as uncertainties between three independent assays performed were lower than 0.5 per thousand. This analytical procedure has then been successfully applied to confirm the contamination of a sediment by the petroleum product spilled by the Erika tanker after its wreck on 12 December 1999 close to the Atlantic Coast of France.

Atlantic Ocean↗

The use of respiratory enzymes as biomarkers of petroleum hydrocarbon exposure in Mytilus edulis planulatus.

The effect of exposure to petroleum hydrocarbons via the water column and through contaminated sediment upon changes in respiratory enzymes in the common mussel (Mytilus edulis planulatus) was investigated. Mussels were exposed to three concentrations of the water-accommodated fraction (WAF) of Bass Strait crude oil, for 24, 48, and 96 h. In a second study mussels were exposed to three concentrations of crude oil-contaminated sediment for 2 weeks and 1, 2, 4 and 6 months. Activities of citrate synthase (CS) and lactate dehydrogenase (LDH) were measured in the gills. In mussels exposed to WAF, a significant decrease in CS activity was observed over time (P<0.05), whereas treatment did not cause a significant change in CS activity (P>0.05); neither treatment nor time had an effect on LDH activity. Exposure to contaminated sediment did not have a significant effect on CS activity, however, time had a significant effect on CS activity (P<0.05). Both time and treatment had an effect on LDH activity (P<0.05). Results demonstrated that changes in gill CS and LDH are not sensitive biomarkers of petroleum hydrocarbon exposure in M. edulis planulatus.

Animals↗

Size-exclusion chromatography of large molecules from coal liquids, petroleum residues, soots, biomass tars and humic substances.

Size-exclusion chromatography (SEC) using 1-methyl-2-pyrrolidinone (NMP) as eluent has been calibrated using various standard polymers and model compounds and applied to the analysis of extracts of coal, petroleum and kerogens, to petroleum vacuum residues, soots, biomass tars and humic substances. Three separate columns of different molecular mass (MM) ranges were used, with detection by UV absorption; an evaporative light scattering detector was used for samples with no UV absorption. Fractionation was useful to separate signal from the less abundant high-mass material, which was normally masked by the strong signal from the more abundant low-mass material in the absence of fractionation. Fractionation methods used to isolate high-mass materials before SEC analysis included planar chromatography, column chromatography and solvent solubility. The apparently large molecules were concentrated into the fractions not soluble in common solvents and were relatively immobile in planar chromatography. All samples and fractions contained some material excluded from the column porosity. Evidence from other techniques suggests that the excluded material is of different structures from that of the resolved material rather than consisting of aggregates of small molecules. We speculate that the excluded material may elute early because the structures of this material are three-dimensional rather than planar or near planar.

Carbon↗

A comparison of DNA profiling techniques for monitoring nutrient impact on microbial community composition during bioremediation of petroleum-contaminated soils.

Amplicon length heterogeneity PCR (LH-PCR) and terminal restriction fragment length polymorphisms (TRFLP) were used to monitor the impact that nutrient amendments had on microbial community dynamics and structural diversity during bioremediation of petroleum-contaminated soils. Slurried soils contaminated with petroleum hydrocarbons were treated in airlift bench-scale bioreactors and were either amended with optimal inorganic nutrients or left unamended. Direct DNA extraction and PCR amplification of whole eubacterial community DNA were performed with universal primers that bracketed the first two or three hypervariable regions of the 16S rDNA gene sequences. The LH-PCR method profiled a more diverse microbial community than did the TRFLP method. The LH-PCR method also tracked differences between the communities due to nutrient amendments. An in silico database search for bacterial genera with amplicon lengths represented in the community fingerprints was performed. It was possible to qualitatively identify different groups in the microbial community based on the amplicon length variations. A similar "virtual" search was performed for the TRFLP fragments using the web-based TAP-TRFLP program. Cloning and sequencing of the PCR products confirmed the in silico database matches. The application of the LH-PCR method as a monitoring tool for bioremediation could greatly enhance and extend the current understanding of the microbial community dynamics during the biodegradation of environmental contaminants.

Bacteria↗

Radon emanation from NORM-contaminated pipe scale and soil at petroleum industry sites.

Radon-222 emanation fractions were determined for barite scale deposits associated with petroleum production tubing and soil contaminated with naturally occurring radioactive material (NORM). Samples were analyzed for 226Ra concentration, the results of which were used to calculate the 222Rn emanation fraction for the sample. An important parameter determining the overall Rn activity flux from a solid medium, 222Rn emanation fraction represents the fraction of 222Rn produced that enters the interconnected pore space within a medium contaminated with 226Ra before the 222Rn undergoes radioactive decay. The primary objective of the study was to determine whether 222Rn emanation fractions from pipe scale and soil from petroleum production sites are similar to those of uranium mill tailings. Pipe scale samples were collected at four sites representing a wide geographical area, and consisted primarily of barite scale where Ra atoms have replaced a fraction of the Ba within the crystal lattice of the scale. Soil samples were collected at five sites, from areas exhibiting elevated surface gamma exposure rates indicating the presence of NORM. For comparison, 226Ra concentrations and 222Rn emanation fraction were also determined for uranium mill tailings samples provided from a site in Utah. Although 2226Ra concentrations from pipe scale samples were similar to those found in uranium mill tailings, 222Rn emanation fractions from scale were generally lower. Emanation fractions from each data set were statistically different from those of mill tailings (p < or = 0.01). The differences are probably due to physical differences between the two media and to the method by which the Ra is deposited in the material. Radon emanation from soils was extremely variable owing not only to differences in physical and chemical soil properties, but also to the means by which NORM has entered the soil. Although additional emanation measurements from other sites are needed, the data collected at these sites indicate that regulations intended to protect human health from 222Rn inhalation should consider the type and properties of the medium in which the NORM is contained, rather than relying strictly on concentrations of the parent 226Ra.

Industry↗

Gas chromatographic determination for forensic purposes of petroleum fuel inhaled just before fatal burning.

The determination of petroleum fuel in the blood of burned bodies was carried out by three different gas chromatographic procedures. Seven components of gasoline (isopentane, n-pentane, 2-methylpentane, benzene, 2-methylhexane, 3-methylhexane and toluene) and five of kerosene (xylene, C9H20, mesitylene, pseudocumene and C11H24) were chosen as indicators with a coefficient of variation of 5-24%. The methods were applied to four autopsy cases with a relatively low carboxyhaemoglobin (HbCO) content. When gasoline exposure had occurred, the blood concentrations determined were almost identical whatever the components selected. Great variations in the components determined were found after kerosene exposure, and hydrocarbons greater than or equal to C14 were hardly inhaled by the victims. A higher content of fuel in the left than in the right ventricular blood observed in the autopsy cases suggests fuel inhalation just before death. The same phenomenon was also observed in the content of blood HbCO. Determinations of petroleum fuel and HbCO in both the right and left ventricular blood would be useful for the forensic diagnosis on burned bodies with a low HbCO content.

Aged↗

Quantification and interpretation of total petroleum hydrocarbons in sediment samples by a GC/MS method and comparison with EPA 418.1 and a rapid field method.

Total petroleum hydrocarbons (TPH) as a lumped parameter can be easily and rapidly measured or monitored. Despite interpretational problems, it has become an accepted regulatory benchmark used widely to evaluate the extent of petroleum product contamination. Three currently used methods (GC/MS, conventional EPA 418.1, and a rapid field method PetroFLAG) were performed to quantify the TPH content in samples collected from a site contaminated by transformer oil. To standardize the method and improve the comparability of TPH data, crucial GC-based quantification issues were examined, e.g., quantification based on internal standards (ISTD) vs external standards (ESTD), single vs multiple ISTD, and various area integration approaches. The interpretation of hydrocarbon chromatographic results was examined in the context of field samples. The performance of the GC/MS method was compared with those of EPA 418.1 and PetroFLAG. As a result, it was observed that the ISTD quantification method was preferred to the ESTD method, multiple ISTD might be better than single ISTD, and three different area integration approaches did not have a significant effect on TPH results. Evaluation of the chromatograms between a reference sample and three unknown samples showed that the extent of contamination varied appreciably with sample depth. It was also found that there existed a good positive correlation between GC/MS and both EPA 418.1 and PetroFLAG, and that EPA 418.1 produced the higher overall estimate while GC/MS and PetroFLAG resulted in lower, more statistically comparable TPH values.

Chemistry Techniques, Analytical↗

Estimate of mercury emissions to the atmosphere from petroleum.

An estimate of the contribution of mercury to the atmospheric environment from petroleum processed in the United States is constructed from recent data. The estimate is based on a mass balance approach for mercury in crude oil, in refined products, and in waste streams (air, water, solid waste) from refineries. Although there are insufficient data at present to have a high degree of confidence in the mean amount and range of mercury concentrations in crude oil or in refined products, the framework of the estimate should assist direction for the acquisition of additional data. On the basis of selected data that put the estimated mean concentration of total mercury in crude oil close to 10 ppb, it is calculated that the total amount of mercury in U.S. petroleum processed yearly is slightly over 8000 kg/yr. Of this amount, approximately 6000 kg/yr is estimated to be emitted to the atmosphere from combustion of liquid hydrocarbon fuels, which represents about 10% of the U.S. yearly emission rate of atmospheric mercury from coal combustion. The material balance predicts that the amount of mercury in air emissions from all U.S. refineries is on the order of 1500 kg/yr based on the assumption that fugitive mercury emissions from refineries are negligible. Atmospheric emissions of mercury from fuel oil burned in the United States are estimated in the U.S. EPA Mercury Report to Congress to be approximately 10000 kg/yr, and this estimate may be in error on the high side by a factor of 3-10. If the mean amounts of mercury in U.S. distillate and residual fuel oils are in the range of 5-15 ppb, as suggested by more recent data, then U.S. fuel oil combustion should contribute no more that about 1000-3000 kg/yr (emission ratio = 1) of mercury to the atmospheric burden.

Air Pollutants↗

Evaluation of gastrointestinal solubilization of petroleum hydrocarbon residues in soil using an in vitro physiologically based model.

Petroleum hydrocarbon residues in weathered soils may pose risks to humans through the ingestion pathway. To understand the factors controlling their gastrointestinal (GI) absorption, a newly developed experimental extraction protocol was used to model the GI solubility of total petroleum hydrocarbon (TPH) residues in highly weathered soils from different sites. The GI solubility of TPH residues was significantly higher for soil contaminated with diesel than with crude oil. Compared to the solubility of TPH residues during fasted state,the solubility of TPH residues during fat digestion was much greater. Diesel solubility increased from an average of 8% during the "gallbladder empty" phase of fasting (and less than 0.2% during the otherfasting phase) to an average of 16% during fat digestion. For crude oil, the solubility increased from an average of 1.2% during the gallbladder empty phase of fasting (and undetectable during the other fasting phase) to an average of 4.5% during fat digestion. Increasing the concentration of bile salts also increased GI solubility. GI solubility was reduced by soil organic carbon but enhanced by the TPH content.

Absorption↗

Detection of anaerobic metabolites of saturated and aromatic hydrocarbons in petroleum-contaminated aquifers.

Recent investigations have demonstrated that several classes of petroleum hydrocarbons are susceptible to anaerobic decay, including alkanes and mono- and polycyclic aromatic compounds. In previous work, benzylsuccinates were shown to be useful indicators of in situ anaerobic alkylbenzene metabolism. In the present study, we sought to determine whether metabolites of alkanes and naphthalenes could similarly be used as indicators of the intrinsic decomposition of these compounds in petroleum-contaminated aquifers. Such metabolites include succinate derivatives of n-alkanes, cyclic alkanes, and alkylaromatic hydrocarbons as well as naphthoic acids. Using gas chromatography-mass spectrometry (GC-MS), we analyzed trimethylsilyl-derivatized organic extracts from six hydrocarbon-contaminated groundwaters for MS fragment ions indicative of such anaerobic metabolites. Geochemical indicators in these aquifers suggested the prevalence of anaerobic processes. In the groundwaters of the contaminated sites, we found compounds whose MS profiles suggested that they were indeed alkylsuccinic acids, ranging from C3 to C11 succinates. Propyl-, hexyl-, octyl-, and decylsuccinic acids were positively identified in the groundwaters by GC-MS matches with chemical or biologically produced standards. In two of the aquifers, we also detected components whose MS profiles matched with authentic standards of naphthoic acids and tetrahydronaphthoic acids. Metabolites were detected in nanomolar concentrations. The finding of these putative anaerobic metabolites of alkanes and naphthalenes signifies the in situ biodegradation of these hydrocarbons and attests to their value as indicators of intrinsic bioremediation.

Anaerobiosis↗

The West Falmouth oil spill after thirty years: the persistence of petroleum hydrocarbons in marsh sediments.

The long-term fate of petroleum hydrocarbons in marsh sediments (West Falmouth, MA) contaminated in 1969 by the spill of the barge Florida was investigated. A 36-cm-long sediment core was collected in August 2000, and sediment extracts were analyzed by gas chromatography (GC) and comprehensive two-dimensional gas chromatography (GC x GC). The latter technique is capable of separating 1 order of magnitude more compounds than the former and was used to observe whether any compositional changes in the unresolved complex mixture (UCM) occurred. No evidence of petroleum residues was detected in the top 6 cm (0-6 cm) and the lower 8 cm (28-36 cm) of the core. However, the central sections 16-28 cm) were dominated by a UCM in the boiling range of n-C13-n-C25 alkanes, consistent with a No. 2 fuel oil source. The 12-14- and 14-16-cm sections had the highest concentrations of UCM approximately 8 mg g(-1)). These values are similar to concentrations observed shortly after the spill. Initial GC x GC analysis revealed that only the n-alkanes were completely degraded, and contrary to previous studies, pristane and phytane as well as numerous other branched alkanes are still present in the sediments. These results suggestthatatthis site hydrocarbon contamination will persist indefinitely in the sedimentary record.

Accidents↗